[SUREFIRE-1962] Unit test for ProviderInfo#isApplicable

[slawekjaranowski]

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[Tibor17]

The call new TestNgProviderInfo( null ).isApplicable() returns false. We call new DynamicProviderInfo( null ).isApplicable() but it returns true. The impl in DynamicProviderInfo should be a bit more similar to other impl of ProviderInfo and it should not only return the same value without the null check at least.

[Tibor17]

If you read the name of method like a news autoDetectOneWellKnownProvider() it says that one should be detected. We use to return List<ProviderInfo>. I know why it is. It simplifies the caller but it is not alright. If we have returned Optional<ProviderInfo> the method would be called easily .map(singletonList()).orElse(emptyList()) with Java 8.

[slawekjaranowski]

changes for DynamicProviderInfo implementation should be done in separate PR with new issue.

also changing for autoDetectOneWellKnownProvider method is out of scope for this PR.

[Tibor17]

@slawekjaranowski Your tests have discovered these cosmetic issues, so yes, pls open new tickets.

[slawekjaranowski]

issues created and linked

[slawekjaranowski]

@Tibor17 Do we want to merge it? I need rebase it.

[slawekjaranowski]

@Tibor17 - ping